1. Field of the Invention
The present invention relates to an information processing device, an importance calculation method, and a program.
2. Description of the Related Art
With recent development of information and communications technology, various kinds of contents such as music, videos, electronic book, news articles, product information or event information are provided to users over a network. It is, however, not easy for an individual user to find suitable information from such enormous contents. Therefore, search services such as keyword search or genre search that support a user to find a content, recommendation services that recommend a content suitable for a user by a system and so on are provided. For example, Japanese Unexamined Patent Application Publication No. 2007-323315 describes a technique called collaborative filtering adopted to many content recommendation services. Further, Japanese Unexamined Patent Application Publication No. 2007-200339 describes a technique that decides a TV program to be recommended by using matching based on a vector space model.
In the above-described content search services, content recommendation services and other content-related services, a key factor determining the effectiveness of a service is handling of attributes of a content. Generally, the attributes of a content include different kinds such as an attribute artificially given to the content, an attribute generated by analyzing content data, and an attribute calculated based on a user action on the content. At present, not only the number of contents provided to a user but also the variety of attributes of contents to be handled in services is increasing. Consequently, a technique of efficiently extracting an attribute important for classification, search or recommendation of a content from attributes of the content attracts attention. For example, Japanese Unexamined Patent Application Publication No. H9-325969 describes an example of the technique for extracting an important attribute from a plurality of attributes for data classified into categories.